POSS-based hybrid thermosets via photoinduced copper-catalyzed azide-alkyne cycloaddition click chemistry

An efficient approach for the preparation of inorganic/organic hybrid thermosets via photoinduced copper-catalyzed azide-alkyne cycloaddition click chemistry is established. Highly cross-linked thermoset polymers have been practically obtained by this technique using-multifunctional compounds, tri-alkyne (1,1,1-tris[4-(2-propynyloxy) phenyl]-ethane) with octakis-azido-POSS or tri-azide (3,3'-((2-((3-azido-2-hydroxypropoxy) methyl)-2-ethylpropane-1,3-diyl) bis(oxy)) bis(1-azidopropan-2-ol)) in the presence of Cu(II) Br-2/N, N, N', N ''., N '''.-pentamethyldiethylenetriamine/2-dimethoxy-2-phenyl acetophenone. The homogeneously distributed POSS nanoparticles are clearly detected in the TEM micrographs; whereas the TGA analysis shows that the obtained hybrid thermosets are thermally stable up to 360 degrees C and begin to lose weight at higher temperatures with a char yield of 23-50% at 800 degrees C.